The present invention relates to loaders, and particular to a system for loading retorts, sterilization systems, and the like. The preferred embodiment of the present system provides both loading and unloading modules, the loading module designed to automatically load fragile containers, in mass and by layer into a unique self-supporting cube array of stacked trays (hereinafter referred to as batch cube which remain intact and are conveyed to and from the unloaders by a basket frame. The unloader module automatically unloads the containers after the cube array and its contents have been processed, in layer-by-layer fashion.
The batch cube remains intact as a stacked unit throughout the entire retort process, transported and enveloped by a basket frame. A hydraulic ram which is associated with each the loader and unloader, indexing the batch cube vertically during the loading/unloading process. Each layer in the stack of trays forming the batch cube is either loaded or unloaded as that layer is positioned in the home position. Both the loader and unloader includes home position locating devices or tray supports that accurately position the tray or cube array out of the basket frame and to the appropriate position so that product can be transferred onto or off of the conveyor.
In the loader module, a multi-position container break is used to collate product prior to transfer into the tray system. There are a total of three break locations. A clearing assembly is provided to assure that no containers are left on the dead plate.
Lastly, a tip indicator is taught wherein the unit is able to detect when containers which have been knocked over or are otherwise improperly oriented with regard to the cube array during the loading thereof.
Most shelf stable products have historically been processed in metal cans or glass containers, which are typically processed in a mass in a retort basket or the like. These containers are very rigid and not prone to damage when using conventional retort basket loading techniques. These containers are rigid enough that each layer can be stacked in the basket upon the previous layer with no damage to the containers in the lower quadrant of the stack. Perforated layer pads or divider sheets are typically placed between each layer to separate same.
Because of consumer preferences and lesser costs, flexible and fragile containers have begun to be used in increasing numbers. This trend started in the mid 1980 s and has increased significantly starting in the late 1990 s. As the consumer demand for this type of packaging increases, food processors have been faced with the difficult chore of handling these containers at higher and higher line speeds.
Unlike a rigid container like a metal can or glass bottle, these containers cannot support the weight of additional containers being loaded one layer on top the next. Examples of fragile containers include plastic bottles, trays, cans, cups, and bowls, and various laminated packaging. The geometry of these packages can include cylindrical, rectangular, and various other irregular shaped containers. Since most production lines require elevated line speeds to be commercially feasible, the best method to transfer or load these types of containers is to do so in mass. However, the prior art fails to provide such a system.
Existing loading devices that have been used to handle flexible pouches and some fragile containers use a pick and place methodology, which may or may not allow for a full layer of containers to be handled at one time. In addition to handling the container, this type of handling approach also requires secondary handling of the trays. Each layer must be staged for loading or unloading and then collated into a formed stack. There is also additional handling, which must be done to manage the flow of racks between the unloader and loader. All of this secondary handling makes the equipment design more complex, more costly, and in many cases limits the operational speed of the line.
Unlike the prior art, the present invention seeks to provide a system for the loading and unloading of fragile containers which cannot be stacked upon one another which is reliable and fast in operation, and relatively cost effective to operate and maintain.
In this regard, the present invention provides a system for loading and unloading fragile containers for the retort or sterilization process in a manner that will eliminate the damaging vertical, downward forces that cause container deformation and do so at commercially accepted line speeds. The invention eliminates the unnecessary complexities and costs seen with secondary tray handling currently being utilized.
The present invention provides an apparatus suitable for handling multiple containers types including: plastic bottles, plastic cans, plastic cups, and various laminated packaging. The geometry of these packages can include cylindrical, rectangular, and various other irregular shaped containers. The containers can be handled either in lanes or in a nested pattern. The invention is applicable for any type of horizontal retort which uses square or rectangular baskets.
The methodology used in this invention is to handle the transfer one full layer at a time in a specialized, one piece, multi-layer transport and processing cube array. While the array is referred to as being a cube shape, this is not meant to be limiting, as the array can comprise any rectilinear or other configuration, depending upon the application. The number of containers to be treated in a layer is a function of the size of the container being loaded and the size of the cube or basket that will fit inside the retort or sterilizer. The methodology used in the invention allows the stack of trays that forms the batch cube to always stay together.
Thus, the need for secondary handling (i.e., stacking the goods to be treated upon one another in a layering manner) is completely eliminated. The batch cube can either be contained within a basket or basket frame, as illustrated in the preferred embodiment of the present invention. As will be shown, the trays can include lanes which allow the product to be staged by lanes or can have an open configuration which allows for a nested pattern of containers.
In either case, the cube of trays is indexed up and down and stops at the home position so that the layer of containers can be transferred. Each layer in the cube will visit the home position until the entire cube is emptied or filled. The side loading of the trays cube is what allows the cube to stay together as a unit and eliminates the need to stack and de-stack the cube like what is done with pick and place systems.
The invention includes both a loading module and unloading module. Both modules are almost identical with the exception of the direction of operation and a few components like the break feature. This fact aids in the economy of both the fabrication and the ongoing operation of the modules. Both modules are controlled by an independent PC or PLC. The PC or PLC controls allow for fully automatic operation of the machines.
Both the loader and unloader module include an independent, servomotor driven, linear motion mechanism used to push the containers into or out of the tray a Pusher. Another independent, servomotor driven, linear motion mechanism is used as a follower to assure that containers are not tipped during the transfer process a Follower. This feature is required if the modules are to be operated without the presence of a human operator. Both the Pusher and Follower are equipped with a breakaway mechanism that will trip in the event that a container is tipped over. Both breakaway mechanisms are equipped with a detection switch that sends a tipped container signal to the PLC or PC controlling the modules.
Both the loader and unloader module can include components for determining the accurate location of the tray cube, including proximity switches, photosensors, or other tracking means. The hydraulic ram mechanism is used to provide coarse positioning of the cube within the module, lifting the cube from the basket frame so that the tray to be loaded is in the appropriate position. Atray support mechanism is used for final and accurate positioning of the layer being loaded or unloaded. This part of the mechanism is essential to assure a final, accurate location prior to container transfer. The mechanism eliminates cumulative dimensional error within the cube and provides needed support for trays and basket frame so that deflection error is also eliminated.
A multi-position can brake is used in the loader module to allow proper staging of each layer of containers into the tray to be loaded. Unlike conventional brakes (which may use, for example, pick and place loading techniques), the present invention utilizes linear, horizontal motion to convey the product into the trays, which eliminates the damaging effects of a top pressure brake used for metal cans or other rigid containers.
A conveyor is used to transport the cubes to and from each module. This conveyor is oriented transverse to each module and straddles the hydraulic push mechanism. The push plate actuates up and down through the conveyor frame and allows the cube to be moved for positioning at the load or unload position.
The above components working together form a new and innovative loading/unloading system which is not contemplated or otherwise suggested by the prior art.
It is therefore an object of the present invention to provide a loading/unloading system for retorts or sterilizers which can accommodate the new generation of polymer, laminated, or other containers which cannot be stacked upon one another.
It is another object of the present invention to provide a loading/unloading module which automatically loads fragile containers to a multi-shelf, multi-channel cube of trays in a basket frame.
It is another object of the present invention to provide a tip mechanism which indicates if an object being loaded is improperly oriented.
It is another object of the present invention to provide a loader/unloader system which fully automates the process and limits secondary handling of the trays, and wherein the nested trays or batch cube remains intact through the treatment process.
Lastly, it is still another object of the present invention to provide a loader/unloader for fragile containers which is cost effective to implement and maintain, reliable in operation, while providing a speed and operational performance on par with loaders for rigid goods.